How do I add a bar at the bottom of the desktop?

Hello everyone! Nice to meet you.

First, I have to say that I am rather new to xfce, and to Linux in general, so please forgive all the newbie-questions I am probably going to ask.

I saw on some screenshots, what can be done with xfce, and therefore, I wanted to do that too, but well, even after looking at all the possibilities you have from the settings windows, I couldn't find how this could be done.

In some Screenshots I saw, there was a big bar at the bottom of the desktop, a bit like Apple Mac style, which is, if those pictures weren't mistakingly labeld "linux" when they were Mac in fact.

The poster of this picture claims that this is XFCE. Since I love the 2D-oversized version of the TUX penguin with the big eyes, I immediatly wanted to change my desktop to this, but until now, I know neither how to add this bar, nor how to disable the bars at the top and bottom which are already included in the xfce desktop, nor how to find those loveable tuxes.